Tuberculosis (TB) is a communicable disease usually caused by tubercle bacillus (MTB) bacteria. Tuberculosis generally affects the lungs, but also can affect other parts of the body. Most infections show no symptoms, during which case it's referred to as latent tuberculosis. TB is spread from person to person through the air. When people with lung TB cough, sneeze or spit, they propel the TB germs into the air. An individual must inhale only a couple of of those germs to become infected. A review is a piece of writing that summarizes the present state of understanding on a subject. A journal may be a scholarly publication containing articles written by researchers, professors and other experts. Journals specialise in a selected discipline or field of study. Unlike newspapers and magazines, journals are intended for a tutorial or technical audience, not general readers. Journals are published on a daily basis (monthly, quarterly, etc.) and are sequentially numbered. Each copy may be a n issue; a group of issues makes a volume (usually annually is a separate volume).